I like bubble games, and even ones that are repetitive - but this was awful. One more than one occasion, the bubble that I shot didn't go to where I had aimed, (and from what I can see from prvious comments, I am not the only one to have seen this). I'd suggest that is something that you look into.
Also, I felt that this wasn't a game to win, more like a see how long you can go before losing, because extra levels kept being added on at certain times (usually, I noticed, when the bubble missed it's target, which wasn't my fault, and may be a bug, but also when I didn't have the right bubble to shoot.)
I found the fact that I couldn't apparently change the bubble to a different colour, even though you had very kindly revealed my next to options.
But I felt that the game was rigged in favour of me not winning, or rather in favour of seeing how long I can go until I lose.
Same old, Same old
I couldn't help but feel like every shot was either too far left, or too far right of where I was aiming. The music... glad there's a mute button. And as the previous reviewer stated, kill the cuteness of the balls/bubbles.
Kill the cute balls. That's it.